Re: [Haskell-beginners] How to construct complex string

8 Aug 2013

      Am 08/06/2013 07:01 PM, schrieb Stephen Tetley:
...
Hi Martin
If you are building syntax as a sequence of commands (or statements) a
common idiom is to collect them with a Writer monad.
Andy Gill's Dotgen on Hackage is a nice realization of this idiom. See
the how example included in the package has acceptably nice syntax
without obliging the implementation to use complex facilities such as
Template Haskell.
Thanks Stephen,

exactly the nudge I was looking for, except I could not find any
examples in the package. I had a brief look at the source code and it
did not instantly reveal itself.

Actually I already got stuck here:

data Dot a = Dot { unDot :: Int -> ([GraphElement],Int,a) }

Thanks Brent

for you detailed explanation.

Re: [Haskell-beginners] How to construct complex string

martin